Semiconductor devices are widely adopted in various applications. As a result, user demands for higher performance and functionality have steadily increased. For example, a compressor with frequency conversion is expected to be capable of reducing on-resistance, performing high speed switching and maintaining high breakdown voltage. In order to fulfill the requirements, the compressor needs to be equipped with several structures such as super junctions.
The super junction structure is constructed by alternately arranging an n-type impurity area and a p-type impurity area constituting a p-n column pair. Usually, several processes, such as multiple etching, implanting and driving-in, are involved in constructing the p-n column pair. However, the implanted area is etched in a way that shapes the impurity region into a jagged contour which is unable to perform the function of the super junction. Thus, a structure or a method for forming the p-n column pair is still in great demand.